/**********
This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)

This library is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
more details.

You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
**********/
// "liveMedia"
// Copyright (c) 1996-2018 Live Networks, Inc.  All rights reserved.
// Transcoder for ADUized MP3 frames
// Implementation

#include "include/MP3ADUTranscoder.hh"
#include "MP3Internals.hh"
#include <string.h>

MP3ADUTranscoder::MP3ADUTranscoder(UsageEnvironment &env,
                                   unsigned outBitrate /* in kbps */,
                                   FramedSource *inputSource)
        : FramedFilter(env, inputSource),
          fOutBitrate(outBitrate),
          fAvailableBytesForBackpointer(0),
          fOrigADU(new unsigned char[MAX_MP3_FRAME_SIZE]) {
}

MP3ADUTranscoder::~MP3ADUTranscoder() {
    delete[] fOrigADU;
}

MP3ADUTranscoder *MP3ADUTranscoder::createNew(UsageEnvironment &env,
                                              unsigned outBitrate /* in kbps */,
                                              FramedSource *inputSource) {
    // The source must be an MP3 ADU source:
    if (strcmp(inputSource->MIMEtype(), "audio/MPA-ROBUST") != 0) {
        env.setResultMsg(inputSource->name(), " is not an MP3 ADU source");
        return NULL;
    }

    return new MP3ADUTranscoder(env, outBitrate, inputSource);
}

void MP3ADUTranscoder::getAttributes() const {
    // Begin by getting the attributes from our input source:
    fInputSource->getAttributes();

    // Then modify them by appending the corrected bandwidth
    char buffer[30];
    sprintf(buffer, " bandwidth %d", outBitrate());
    envir().appendToResultMsg(buffer);
}

void MP3ADUTranscoder::doGetNextFrame() {
    fInputSource->getNextFrame(fOrigADU, MAX_MP3_FRAME_SIZE,
                               afterGettingFrame, this, handleClosure, this);
}

void MP3ADUTranscoder::afterGettingFrame(void *clientData,
                                         unsigned numBytesRead,
                                         unsigned numTruncatedBytes,
                                         struct timeval presentationTime,
                                         unsigned durationInMicroseconds) {
    MP3ADUTranscoder *transcoder = (MP3ADUTranscoder *) clientData;
    transcoder->afterGettingFrame1(numBytesRead, numTruncatedBytes,
                                   presentationTime, durationInMicroseconds);
}

void MP3ADUTranscoder::afterGettingFrame1(unsigned numBytesRead,
                                          unsigned numTruncatedBytes,
                                          struct timeval presentationTime,
                                          unsigned durationInMicroseconds) {
    fNumTruncatedBytes = numTruncatedBytes; // but can we handle this being >0? #####
    fPresentationTime = presentationTime;
    fDurationInMicroseconds = durationInMicroseconds;
    fFrameSize = TranscodeMP3ADU(fOrigADU, numBytesRead, fOutBitrate,
                                 fTo, fMaxSize, fAvailableBytesForBackpointer);
    if (fFrameSize == 0) { // internal error - bad ADU data?
        handleClosure();
        return;
    }

    // Call our own 'after getting' function.  Because we're not a 'leaf'
    // source, we can call this directly, without risking infinite recursion.
    afterGetting(this);
}
